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authorArnd Bergmann <arnd@arndb.de>2018-12-31 22:22:40 +0100
committerArnd Bergmann <arnd@arndb.de>2019-01-25 17:22:50 +0100
commit275f22148e8720e84b180d9e0cdf8abfd69bac5b (patch)
treef7cb9810f8415904589d73a8d8f3c15b0bc70246 /ipc/msg.c
parent73a66023c937ef258f2aa340cdb53ae7d8b1d47c (diff)
downloadlinux-275f22148e8720e84b180d9e0cdf8abfd69bac5b.tar.bz2
ipc: rename old-style shmctl/semctl/msgctl syscalls
The behavior of these system calls is slightly different between architectures, as determined by the CONFIG_ARCH_WANT_IPC_PARSE_VERSION symbol. Most architectures that implement the split IPC syscalls don't set that symbol and only get the modern version, but alpha, arm, microblaze, mips-n32, mips-n64 and xtensa expect the caller to pass the IPC_64 flag. For the architectures that so far only implement sys_ipc(), i.e. m68k, mips-o32, powerpc, s390, sh, sparc, and x86-32, we want the new behavior when adding the split syscalls, so we need to distinguish between the two groups of architectures. The method I picked for this distinction is to have a separate system call entry point: sys_old_*ctl() now uses ipc_parse_version, while sys_*ctl() does not. The system call tables of the five architectures are changed accordingly. As an additional benefit, we no longer need the configuration specific definition for ipc_parse_version(), it always does the same thing now, but simply won't get called on architectures with the modern interface. A small downside is that on architectures that do set ARCH_WANT_IPC_PARSE_VERSION, we now have an extra set of entry points that are never called. They only add a few bytes of bloat, so it seems better to keep them compared to adding yet another Kconfig symbol. I considered adding new syscall numbers for the IPC_64 variants for consistency, but decided against that for now. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'ipc/msg.c')
-rw-r--r--ipc/msg.c39
1 files changed, 32 insertions, 7 deletions
diff --git a/ipc/msg.c b/ipc/msg.c
index 0833c6405915..8dec945fa030 100644
--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -567,9 +567,8 @@ out_unlock:
return err;
}
-long ksys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf)
+static long ksys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf, int version)
{
- int version;
struct ipc_namespace *ns;
struct msqid64_ds msqid64;
int err;
@@ -577,7 +576,6 @@ long ksys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf)
if (msqid < 0 || cmd < 0)
return -EINVAL;
- version = ipc_parse_version(&cmd);
ns = current->nsproxy->ipc_ns;
switch (cmd) {
@@ -613,9 +611,23 @@ long ksys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf)
SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf)
{
- return ksys_msgctl(msqid, cmd, buf);
+ return ksys_msgctl(msqid, cmd, buf, IPC_64);
}
+#ifdef CONFIG_ARCH_WANT_IPC_PARSE_VERSION
+long ksys_old_msgctl(int msqid, int cmd, struct msqid_ds __user *buf)
+{
+ int version = ipc_parse_version(&cmd);
+
+ return ksys_msgctl(msqid, cmd, buf, version);
+}
+
+SYSCALL_DEFINE3(old_msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf)
+{
+ return ksys_old_msgctl(msqid, cmd, buf);
+}
+#endif
+
#ifdef CONFIG_COMPAT
struct compat_msqid_ds {
@@ -689,12 +701,11 @@ static int copy_compat_msqid_to_user(void __user *buf, struct msqid64_ds *in,
}
}
-long compat_ksys_msgctl(int msqid, int cmd, void __user *uptr)
+static long compat_ksys_msgctl(int msqid, int cmd, void __user *uptr, int version)
{
struct ipc_namespace *ns;
int err;
struct msqid64_ds msqid64;
- int version = compat_ipc_parse_version(&cmd);
ns = current->nsproxy->ipc_ns;
@@ -734,8 +745,22 @@ long compat_ksys_msgctl(int msqid, int cmd, void __user *uptr)
COMPAT_SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, void __user *, uptr)
{
- return compat_ksys_msgctl(msqid, cmd, uptr);
+ return compat_ksys_msgctl(msqid, cmd, uptr, IPC_64);
}
+
+#ifdef CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION
+long compat_ksys_old_msgctl(int msqid, int cmd, void __user *uptr)
+{
+ int version = compat_ipc_parse_version(&cmd);
+
+ return compat_ksys_msgctl(msqid, cmd, uptr, version);
+}
+
+COMPAT_SYSCALL_DEFINE3(old_msgctl, int, msqid, int, cmd, void __user *, uptr)
+{
+ return compat_ksys_old_msgctl(msqid, cmd, uptr);
+}
+#endif
#endif
static int testmsg(struct msg_msg *msg, long type, int mode)